Using the method described here, you do not need any local map data. The maps are automatically pulled from OpenStreetMap.
However, you might want use concepts such as regions, and you need to define them through files containing those geolocations. There are multiple sources of data which is freely available, in this example we are using shape files from this location:
http://data.geo.admin.ch.s3.amazonaws.com/ch.swisstopo.swissboundaries3d-kanton-flaeche.fill/data.zip
We have provided the shape files we will use for this demonstration, normally you would need to retrieve and unpack the map data.
There are many file formats commonly used for maps. In this case what we have are a set of shapefiles. Since we will be working with geojson files in this demonstration you need to convert them to geojson.
A sample geojson file has been supplied with this tutorial, but for reference you can create a geojson file from the shape files from a console like this: